• Aim: How do we find the value of a trig function using a calculator? How do we find an angle when given the decimal value of a trig function?

Try these before we begin:

A. sin^2 x + (sin x)(csc x) B. tan s (cot s + csc x)
cos^2 x

Today's lesson will be very simple. We will learn to use the calculator to find the values of trig funcitons when we know the value of an angle and vice versa.

You have found the values of the angles with sin, cos and tan. As you watch this video take notes as to how to find the values of sec, csc and cot. Make sure you have these notes down and you will need to know how to do this.

Video


Now that you have watched a review video, here is how we change from a decimal value to an angle. For example if you have the value of cos x = 0.8988, we use the cos^-1 key to help us find this value. When we use cos^-1 (this is called the arccos) we enter, cos^-1 0.8988 we get 25.9922183. We round to whatever place-value the directions say.

  • Homework: Complete #3-49 odd, skip # 21, 23, 25 27,

8.7_Calculator_Trig_Values.JPG

  • Answers

A-8.7_Calculator_Trig_Values.JPG